gstack/docs/gstack-2/HOST-COMPATIBILITY.md

GStack 2 host compatibility

This matrix uses evidence tiers. It does not call a host “supported” merely because its directory name exists in legacy setup code.

Tiers

Tier	Meaning
Portable	The canonical skills/<name>/SKILL.md tree follows the Agent Skills specification and uses no required host-private placement logic. This is a source-format claim.
Verified	The named layer and matrix cells passed against a recorded host/installer version. A scoped “Verified — installer” claim does not imply the host UI launched or executed judgment.
Native	A necessary host API adds behavior unavailable through portable skills while consuming the same canonical judgment source. Native is not “better”; it carries an additional adapter maintenance contract.

Tiers are cumulative only when evidence says so. A portable host is not automatically verified. A legacy generated host output is not a native GStack 2 bundle.

Canonical installation

npx skills add time-attack/gstack

The standards installer owns host detection, destination paths, project/global scope, copy versus symlink, updates, removal, and selected-skill installation. Review its detected-host prompt; detection must never silently enroll a host.

Examples supported by the installer interface:

# One public skill only (point selection at the canonical skill directory)
npx skills add time-attack/gstack/skills --skill qa

# Installer-managed global scope
npx skills add time-attack/gstack -g

Run npx skills add --help for the installed CLI version before scripting agent-selection flags. GStack deliberately does not reproduce those flags or host paths in ./setup.

The expected discoverable names are exactly:

plan
design
qa
debug
review
ship

compat/*.md and references/legacy/*.md are not SKILL.md files and must not appear as additional skills. Installing a subset must not pull the other five public entries unless the user selected them.

With skills CLI 1.5.19, the repository-root --list result is exactly these six names. For selected installation, use the canonical skills/ source as in the example above. That CLI version's pre-filter display can count hidden compatibility aliases, but the committed actual-host artifact proves that only the selected qa directory was installed; the display count is not an installed-skill count.

Candidate installer matrix

The isolated standard-installer matrix passed 510/510 checks with skills CLI 1.5.19: 18 install cases and two removal cases. Default discovery projected only canonical skills/; separate explicit-selection cases covered a single canonical skill and an opt-in legacy alias. The matrix used symlinked and spaced source paths matching a clean checkout where ignored legacy host trees are absent. Every installed file was a physical copy and its hash matched the selected source. The standard skill installation remains Markdown-only and does not install the optional runtime. The committed evidence artifact is evals/installation/install-matrix.json.

Host	Portable	Project all-six	Global all-six	Selected-skill coverage	Installer tier	Host UI/process
Claude Code	yes	pass	pass	no separate subset case	Verified — installer	pending
OpenAI Codex	yes	pass	pass	global qa, review, ship pass + removal pass; actual selected qa runtime-absent run; opt-in alias covered	Verified — installer; runtime-absent invocation passed	live v1/v2/v3 failed; v3 was 3/4
Kimi Code CLI	yes	pass	pass	no separate subset case	Verified — installer	browser automation uses the consented GStack local-browser fallback; host skill invocation pending
Cursor	yes	pass	pass	project qa, review, ship pass + removal pass	Verified — installer	pending
Pi	yes	pass	pass	no separate subset case	Verified — installer	pending
OpenClaw	yes	pass	pass	project ship single-skill pass	Verified — installer	pending
GitHub Copilot	yes	pass	pass	no separate subset case	Verified — installer	pending

The representative selection cases installed exactly qa, review, and ship, independently at project scope for Cursor and global scope for Codex, then removed them noninteractively. Separate cases installed only ship for OpenClaw and explicitly selected the office-hours compatibility alias for Codex; neither alias nor unselected canonical skill was silently enrolled. --copy was advertised and used.

This is filesystem/installer verification, not a claim that seven host UIs loaded or executed the skills. A separate actual Codex invocation installed only qa from time-attack/gstack/skills, with the optional runtime absent, and passed the judgment/setup-gate behavior without changing its workspace or creating a runtime or browser. The Codex adversarial lane still has no passing live result: v1 and immutable v2 failed; the v3 offline harness is green at 18 tests / 111 assertions, but paid live v3 was a one-shot 3/4 failure because review failed compound inspection. It was not retried or relabeled. The installer matrix used the current local canonical projection through the published npx skills CLI. The release branch remained unpushed; native CI used the temporary codex/gstack-2-ci-20260717-39bc307b ref only.

Legacy generators currently know ten host names. That is historical breadth, not proof that all ten install correctly. Kiro's old Codex-rewrite behavior and other host-output transforms are outside the canonical 2.0 path.

Verification procedure and evidence

Use a clean temporary home and project for every cell; never test against an operator's live skill directory.

1. Record OS, host version, Node/npm version, and skills CLI version.
2. List the source and assert exactly six default entries.
3. Install all six at project scope and verify each host discovers only those six GStack public skills.
4. Remove them through the standard installer.
5. Repeat at global scope.
6. Install a selected subset; verify unselected skills were not enrolled.
7. Reinstall/update without re-detecting or enrolling an unselected host.
8. Invoke a pure judgment mode with gstack absent from PATH.
9. Invoke a capability-dependent mode and verify one actionable runtime offer, without breaking judgment.
10. Exercise a path containing spaces and, where supported, symlink and read-only failure behavior.
11. Record exact command, exit status, output artifact, and cleanup result in TEST-EVIDENCE.md.

The automated filesystem portion is:

bun test test/gstack2-installation.test.ts
bun run scripts/gstack2/test-install-matrix.ts --full \
  --output /tmp/gstack2-install-matrix.json

The current matrix passed 510/510 installer CLI checks across 18 installs and two removals; its JSON artifact is committed at evals/installation/install-matrix.json. Steps 8–9 passed for the recorded Codex runtime-absent invocation; actual UI loading for the other representative hosts remains separate. The paid live v3 adversarial run is retained as a failed 3/4 gate, not a pending run. Evidence: standard-codex-runtime-absent-2026-07-17.json and 2026-07-17T19-48-45Z-v3-live-gpt-5-4.json.

Optional runtime/platform matrix

The optional runtime is separate from skill placement. From a repository checkout, the one host-neutral setup entrypoint is:

./setup
~/.gstack/bin/gstack doctor --json

./setup resolves a symlinked checkout, reinstalls the frozen production dependency set on every run, builds missing allowlisted capabilities through the runtime-only build target, validates and hashes every staged file, smoke-tests the CLI, atomically activates the version, and writes stable POSIX and Windows launchers under $GSTACK_HOME/bin (default ~/.gstack/bin). The bundle uses .exe targets on Windows and includes the CoreDevice/iOS bundle only on Darwin. Add the bin directory to PATH if the short gstack command is desired.

Official bundles capture the pinned Bun 1.3.14 executable inside the immutable runtime and expose it as $GSTACK_HOME/bin/bun; browser/design/PDF launchers do not use host-global Bun. Node remains the bootstrap/launcher floor. On Windows, Git for Windows Bash is required only for retained shell helpers and is a separate doctor check. Python 3 is an optional prerequisite only for specialist flows that name it. Doctor reports both tools independently of native browser/design/PDF readiness.

Twenty-five focused installer tests pass with 341 assertions. They cover manifests, paths with spaces, source-root symlinks, internal-link/path-escape rejection, failed build/ validation/smoke rollback including native-load rollback smoke, interrupted-pointer recovery, stable POSIX/Windows launchers, runtime-only builder selection, deterministic exact Sharp/ngrok platform closure, managed uninstall, and the host-neutral wrapper.

The deterministic clean macOS arm64 managed-bundle audit records 110 components, 1,829 files, 450,044,315 bytes, and 50 capability launchers. This is a platform-specific bundle measurement, not a universal byte count; platform-native package payloads differ. Setup installs frozen production-only dependencies and excludes the development-only Claude Agent SDK. The Sharp/ngrok closure is included. The Hugging Face sidecar is excluded and its package is development-only, so setup installs neither its inference runtime nor model weights and reports the L4 capability unavailable.

Platform	Source-level target	Candidate evidence
macOS	Node runtime + local browser + physical iOS where applicable	Runtime installer 25/341 and the deterministic clean macOS arm64 bundle audit pass. The final native job passed 150/0 with 1,189 assertions. The uninterrupted broad singleton run is green at 6,255 pass / 226 expected skips / 0 fail and 25,509 assertions across 384 files. The physical lane later passed 12/12 harness checks and five-of-five live iterations on an explicitly authorized wired paired iPhone17,1; this is device-specific evidence, not universal iOS coverage. Artifact: ios-physical-device-2026-07-20T17-49-19-302Z.json.
Linux	Node runtime + local browser	Official release artifacts currently target glibc on x64 and arm64; musl is rejected before network and is not claimed. Final native Ubuntu passed 150/0 with 1,189 assertions across 16 files. A clean glibc Linux arm64 container also passed the production-only runtime/browser lifecycle.
Native Windows	Node bootstrap/launcher; managed Bun; native browser/design/PDF. Git for Windows Bash only for retained shell helpers; Python 3 only for labeled specialist flows.	Doctor verifies and discloses Bun, Bash, and Python separately. Final native Windows passed 150/0 with 1,145 assertions across 16 files and standard-installer discovery found exactly six skills. The local Windows-safe singleton lane also passed 2,829 / 57 expected skips / 0 fail with 8,648 assertions across all 214 selected files. The older run predates the managed-Bun release artifact, so the new six-target release workflow remains the evidence gate for that layer.
Dev Container	Pure skills and optional runtime; browser only when container supports it	The declared image built; the GStack 2 suite passed 150/0 with 1,188 assertions across 16 files, followed by the clean runtime install/browser smoke and state-preserving uninstall.

Native CI run 29615621805 passed every job at commit a8a5fa1aa381f9b948dfc57af26016092fc33277: macOS, Ubuntu, native Windows, the 470-check installer matrix, and the Dev Container. The sanitized committed record is evals/ci/native-2026-07-17.json. Runs 29608904265, 29611504979, 29611757175, 29612056517 (cancelled), 29613668419, 29614448170, and 29614899434 are retained as superseded diagnostic evidence, not substituted for the passing run.

The six portable skills remain useful when runtime installation fails. A runtime failure must not remove or corrupt their standard-installer placement.

Native adapters

No GStack 2 native tier is currently required or awarded. A future native bundle needs an accepted issue showing that a host API is necessary, must load the same canonical judgment modules, and must pass the portable parity suite. Host-specific presentation metadata such as agents/openai.yaml does not by itself create a second judgment source or a Native claim.